Synthesis of amphiphilic block copolymers by atom transfer radical polymerization

Polystyrene single-capped with halogen, PS-X, was synthesized by atom transfer radical polymerization (ATRP) method using ethyl-alpha-bromopropionate(EPN-Br) as initiator and CuCl/2,2'-bipyridine (bpy) as catalyst and ligand at 110degreesC. By using PS-X as macroinitiator and CuCl/1, 1, 4, 7, 7-penta-methyldiethylenetri-amine (PMDETA) or bpy as catalyst and ligand at 110degreesC, ATRP of N, N-dimethylaerylamide ( DMAA) was realized and functional amphiphilic block copolymers of poly( styrene-block-N,N-dimethylacrylamide) (PS-b-PDMAA) were synthesized. Furthermore, some factors including the molecular weight of macroinitiator, various solvents and ligand that influence the polymerization of DMAA have been studied. The properties of the PS-b-PDMAA copolymer were characterized by using GPC,IR and H-1-NMR analysis.